Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754758AbaKRT2I (ORCPT ); Tue, 18 Nov 2014 14:28:08 -0500 Received: from www.linutronix.de ([62.245.132.108]:41058 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754066AbaKRT2F (ORCPT ); Tue, 18 Nov 2014 14:28:05 -0500 Date: Tue, 18 Nov 2014 20:28:01 +0100 (CET) From: Thomas Gleixner To: Linus Torvalds cc: Dave Jones , Linux Kernel , the arch/x86 maintainers , Don Zickus Subject: Re: frequent lockups in 3.18rc4 In-Reply-To: Message-ID: References: <20141115213405.GA31971@redhat.com> <20141116014006.GA5016@redhat.com> <20141117170359.GA1382@redhat.com> <20141118020959.GA2091@redhat.com> <20141118023930.GA2871@redhat.com> <20141118145234.GA7487@redhat.com> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 18 Nov 2014, Linus Torvalds wrote: > On Tue, Nov 18, 2014 at 6:52 AM, Dave Jones wrote: > > > > Here's the first hit. Curiously, one cpu is missing. > > That might be the CPU3 that isn't responding to IPIs due to some bug.. > > > NMI watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [trinity-c180:17837] > > RIP: 0010:[] [] bad_range+0x0/0x90 > > Hmm. Something looping in the page allocator? Not waiting for a lock, > but livelocked? I'm not seeing anything here that should trigger the > NMI watchdog at all. > > Can the NMI watchdog get confused somehow? That's the soft lockup detector which runs from the timer interrupt not from NMI. > So it does look like CPU3 is the problem, but sadly, CPU3 is > apparently not listening, and doesn't even react to the NMI, much less As I said in the other mail. It gets the NMI and reacts on it. It's just mangled into the CPU0 backtrace. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/